Rotary electric switch



Nov. 29, 1949 E. J. DOUCETTE ROTARY ELECTRIC SWITCH Filed Jan. 30, 1947 EDMUND DOUCETTE Patented Nov. 29, 1949 ROTARY ELECTRIC SWITCH Edmund J. Doucette, Newark, N. J assignor to The Daven Company, Newark, N; J'., a. corporation of- New Jersey Application January 30, 1947;. Seria-tNo; 725,331

4 Claims.

This invention, relates to electric switches of the rotary type for use in test equipment, portable instruments, inspection set-ups,,experimental circuits and. other uses where a superior type multiple position rotary switchis desirable.

An object of. the present invention is to provide a rotary switch which may bemanufactured in standard sizes for stock. and by adjustment of easily adjusted parts any division or combination up to a predetermined multiplication of the number of teeth on thedetent. gear of the switch may be provided, as well as to provide a switch structure which will permit twice the number of make before break or break, before make operations or circuit controls in a switch as are possible in comparable switches of the same.- size now on the market.

Another object ofv the; invention. is to provide a rotary switch in which by novelpositioning of two or more pawls which co-act with the detent gear of the switch, a multiple number of positions may be provided with a detent gear of a given size and given number of teethor detents thus permitting an increasedv number of switch positions in a switch structure of the present invention over the number possible in a corresponding size switch of the-present approved. type now on the market.

With theseand other objects in view, as may appear from the accompanying specification, the invention consists of various features of construction and combination of parts, which will be first described. in connection with the accompanying drawings, showing a rotary electric switch of a preferred form; embodying theinvention, and the featuresforming the invention will be specifically pointed out in the claims.

In the drawings:

Figure l is a view partly in side-elevation and partly in section of. the-improvedswitch without any wiring connections,- thereoin Figure 2. is across section; through the switch taken on the 1ine.2--2 of Figure. 1.

Figure-3 is a fragmentarylongitudinalsection through theswitchtaken; onthe line 3v--3 of Figure 2.

Figure 4is an. endview of. the, contact-carrying head of the switch and taken. on the line 41 4 of Figure 1.

Referring more, particularly to the drawings through the head I to. the ends 4 of which suitable wires (not shown) may be, connected; The head I, is rigidly connected by a suitable sleeve 5 tothe detent carrying. housing. 6. A shaft 1 is rotatably carried. by the sleeve 5. and extends through the housing. 6. and the. contact carrying head I. The shaft I has movable contacts 8 and 8 thereon which contact respectively with the ring 2 and any one of. the spaced contacts 3. The movable contacts 8 and 9. are carried by and rotate with theshaft 1..

A detent gear ill. is mounted, on the shaft 1 for rotation therewith and the shaft may be rotated by any suitable type. of switch arm as indicated at l l., The detent gear H) has alternate teeth [2 and indentations l3. formed. on its perimeter. Pawls l4 and t5, including carrier structures l6, which rotatably carry rollers H are pivotally connected asshown. at IL8' to-the housing 6. The rollers l! are urged. into perimetral engagement with. the detent gear l0. by springs 19.

The number of teeth [2 and indentations l3 of the detent gear Hiare a predetermined fraction of the number of stationary contacts 3 and in the. construction shown. in the drawings there are half as. many teeth, I2 and. indentations l3 as there are contacts 3. The contacts are spaced apart 15 whereas the teeth I2 and the indentations L3. are spaced 30 apart. The pawls 1'4 and l5v are. arranged so that the axis of the rollers I! will be 15 ofi from adiametrical line through the detent. gear [0,, one being upon one side of the line and the other upon the other side of the line, and thus (as clearly shown in Figure 2 of the drawings) one of the rollers. l1 will be engaging in. one of the indentations ['3 and the other roller will. be riding upon the outer edge of one of the teeth 12; thus the, pawls alternate in holding the. detent gear Ill and; consequently the shaft I and movable contacts 8 and 9, in adjusted positions and by so positioning the pawls relative to each other twice, as many adjustments are permitted with theuse of the, detent and consequentlyan adjustment for each of the contacts 3 which are twice in number tov the number of indentations I3 are provided... Also, with. the positioning of the two pawls M2 L5 on. each side of the die ametrical line through the detent gear and the positioning of the. indentations and of the teeth at 30 apart, 15 movement of the detent is provided to correspond to the 15 separation of the stationary contacts 3.

While inthe drawingstherelation of the number of teeth 42 to.- the stationary contacts 3 and the relation ofv theindentations l 3-to the number of stationary contacts 3 is shown as 1 to 2, it is to be understood that any predetermined numerical relationship may be provided, such as one-third as many teeth and indentations as stationary contacts, without departing from the spirit of the present invention.

Since switches of this type are adaptable for being made up in stock quantities for various uses, it is embodied with means which will provide adjustment of the stops or movement limiting means for limiting the rotation of the detent gear Ill, shaft 1 and movable contacts 8 and 9 within difierent ranges or combinations. To permit this adjustment or variation of the range of movement of the movable elements of the switch, a stop member 20 is carried by the housing 6 and the detent gear I is provided with a plurality of stop pin receiving openings 2| extending therethrough inwardly of the teeth l2 and spaced the same as the teeth |2 about the detent gear, that is, the stop pin receiving holes or openings 2| are spaced at 30 from each other. A stop pin 22 is provided which is a threaded screw or pin of the self-cutting thread type which when it is threaded into one of the openings or holes 2| will cut threads thereon, to hold the pin 22 against accidental displacement. A thirteenth or additional hole is drilled midway between two of the adjacent stop pin receiving holes 2| and this additional stop pin receiving hole is adapted to receive a stop pin 23 which is of the same construction as the stop pin 22. The stop pins 22 and 23 are located to engage the stop member so as to limit the movement of the detent gear II]. By putting the twelve holes or openings 2| at a spacing of and the thirteenth hole which receives the stop pin 23 at 15 permits any division or combinations up to twenty-four on a twelve-toothed detent gear,

that is, namely, twice as many as are now provided in rotary switches of the same or companionable sizes as now in use.

It will be understood that the invention is not to be limited to the specific construction or arrangement of parts shown, but that they may be widely modified within the invention defined by the claims.

What is claimed is:

1. In a rotary switch, the combination of, a contact carrying head, a plurality of spaced stationary contacts on said head, an operating shaft carried by said head, movable contact members carried by said shaft for contact with said stationary contacts, a detent gear on said shaft, a housing for said detent gear, said detent gear constructed and arranged with edgewise indentations and a plurality of stop pin receiving holes each spaced from the adjacent one a number of degrees of a circle corresponding to the spacing of the teeth formed by the said indentations, said detent gear provided with an additional stop pin receiving hole between an adjacent pair of said plurality of stop pin receiving holes, a pair of spring pressed pawls disposed on each side of a diametrical line of the detent gear and engaging said detent gear, said pawls spaced from said diametrical line of the detent gear a number of degrees equal to one-half of the degree spacing of the teeth and indentations of said detent gear whereby when one pawl is engaging an indentation the other will engage a tooth of said detent gear, a stop member carried by said housing, a plurality of removable stop pin members in engagement with said stop pin receiving holes and with said additional stop pin receiving hole to co-act with said stop member and the spring pressed pawls to limit the movement of said detent gear and increase the number of relative combinations between said detent gear and said stationary contacts.

2. In a rotary switch, a contact carrying head, a plurality of spaced stationary contacts carried by said head, an operating shaft, movable contact members carried by said shaft for contact with said stationary contacts, a detent gear on said shaft and provided with alternate teeth and indentations each tooth and each indentation spaced from those adjacent thereto a predetermined number of degrees, a pair of spring pressed pawls disposed one on each side of a diametrical line of the detent, said pawls spaced from said diametrical line a number of degrees equal to one-half of the degree spacing of the teeth and indentations of said detent gear whereby when one pawl is engaging in a detent the other pawl will be engaging a tooth perimeter, the number of teeth and the number of indentations of said detent being a predetermined fraction of the number of said stationary contacts with their spacing in degrees of a circle corresponding in inverse relation with the spacing in degrees of a circle of said stationary contacts, a housing for said detent, a stop member carried by said housing, said detent provided with a plurality of stop pin receiving holes extending therethrough each spaced from an adjacent one a number of degrees of a circle corresponding to the spacing of the teeth of the detent gear, and a stop pin for insertion through said holes for engagement with said stop member to limit the movement of said detent and movable contacts.

3. In a rotary switch, a contact carrying head, a plurality of spaced stationary contacts carried by said head, an operating shaft, movable contact members carried by said shaft for contact with said stationary contacts, a detent gear on said shaft and provided with alternate teeth and indentations each tooth and each indentation spaced from those adjacent thereto a predetermined number of degrees, a pair of spring pressed pawls disposed one on each side of a diametrical line of the detent, said pawls spaced from said diametrical line a number of degrees equal to one-half of the degree spacing of the teeth and indentations of said detent gear whereby when one pawl is engaging in a detent the other pawl will be engaging a tooth perimeter, the number of teeth and the number of indentations of said detent being a predetermined fraction of the number of said stationary contacts with their spacing in degrees of a circle corresponding in inverse relation with the spacing in degrees of a circle of said stationary contacts, a housing for said detent, a stop member carried by said housing, said detent provided with a plurality of stop pin receiving holes extending therethrough each spaced from an adjacent one a number of degrees of a circle corresponding to the spacing of the teeth of the detent gear, and a stop pin for insertion through said holes for engagement with said stop member to limit the movement of said detent and movable contacts, said detent gear provided with a stop pin receiving hole formed therein equidistant between an adjacent pair of said plurality of stop pin receiv ing openings to receive a stop pin whereby an increased plurality of relative combinations between the detent gear and stationary contacts may be obtained.

4. In a rotary switch, a contact carrying head,

a plurality of spaced stationary contacts carried by said head, an operating shaft, movable contact members carried by said shaft for contact with said stationary contacts, a detent gear on said shaft and provided with alternate teeth and identations, each tooth and each indentation spaced from those adjacent thereto a predetermined number of degrees, a pair of spring pressed pawls disposed one on each side of a diametrical line of the detent, said pawls spaced from said diametrical line a number of degrees equal to one-half of the degree spacing of the teeth and indentations of said detent gear whereby when one pawl is engaging in a detent the other pawl will be engaging a tooth perimeter, the teeth and indentations of said detent each being equal in number to one-half the number of stationary contacts and spaced twice the number of degrees apart as the spacing of the stationary contacts, a housing for said detent, a stop member carried by said housing, said detent provided With a plurality of stop pin receiving holes extending therethrough, each of said holes spaced from the adjacent hole a number of degrees of a circle corresponding to the spacing of the teeth of the detent gear, a stop pin for insertion through said holes and for engagement with said stop member to limit the movement of said detent gear and movable contacts, said detent gear provided with a stop pin receiving hole therethrough positioned intermediate an adjacent pair of said plurality of stop pin receiving openings to receive a second stop pin whereby an increased plurality of relative combinations between the detent gear and stationary contacts may be obtained.

EDMUND J. DOUCETTE.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

